Eraser-cleaning machine.



G. U. THOMPSON.

ERASER CLEANING MACHINE.

APPLICATION FILED JVULY 3,1914.

1,163,283. Patenfd De0.7,1915.

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ttarnay- COLUMBIA PLANOORAPH CID-,WASHINGTON, D c.

GRANT U. rnorrrsoiv, or cnnAnraLLs, IO'WA.

ERASER-GLEANING MACHINE.

Specification of Letters Patent.

Patented Dec. "2, rats.

Application filed July 3, 1914. Serial No. 848,791.

To all w ham it may concern :Y

Be it known that I, GRANT U. THOMPSON, a citizen of the United States ofAmerica, and a resident of Cedar Falls, Blackhawk county, Iowa, haveinvented certain new and useful Improvements in Eraser-CleaningMachines, of which the following is a specification.

Myinvention relates to improvements in eraser cleaning machines, and theobject of my improvement is to provide means for diiferentially varyingthe speedsof rotation of the cleaning drum and the air exhaustingfan-wheel in communication therewith, of said machine. This object Ihave accomplished by the means which are hereinafter described andclaimed, and which are illustrated in the accompanying drawing, in whichthe figure is a side elevation of my improved eraser cleaning machine,with the cleaning drum and fan-wheel chamber shown in vertical,longitudinal axial section.

My improved apparatus comprises a supporting frame having the spaced enduprights 18 and 29 connected by means of longitudinal bars on the sides,and having alined hearings on their upper ends adapted to receive therotatable shaft 9, the crank 30 being mounted on the left hand end ofthe said shaft and provided withahandle 31.

The numeral 1 denotes a hollow cylindrical cleaner drum, loosely and.non-slidably mounted on said shaft 9, and having hearing openings in itsopposite heads to receive said shaft 9 therethrough, the left handbearing 20 having an outwardly extending dentated clutch part 21 adaptedto detachably receive dentations 22 on a mat ing clutch sleeve 23, thelatter slidably and non-rotatably mounted on said shaft 9 and providedwith an annular groove. In a bearing 28 in the frame upright 29 issecured a fork 27, in which is i pivotally' mounted the lower end of anend lever 26, whose middle part is formed of detachably connected halfrings 25 having inwardly projecting pins 24, the latter extendingmovably into the clutch part 23. By shifting the lever 26, the saidclutch parts may be brought into or out of engagement with each other todetachably securethe drum 1 to the shaft 9. The clutch-parts 22 and 21,when mated, fix the drum 1 on the shaft 9. The drum may be uncoupledfrom the shaft, when it is desired to use the fan-wheel 7 alone toexhaust dust-laden air from the drum, after the latter is in a state ofrest. In the left-hand endof said drum, a number of small openings 34are arranged about the bearing 20 to serve as air-inlets. The right handhead of the drum 1 has a centrally located inwardly offset part 3 havinga number of orifices or air outlets 4 therein in communication with afan-wheel chamber 8, the latter having an orificed bar 32 in line withthe bearing openings in said drum. A sleeve 6 is rotatably andnonslidably mounted upon the shaft 9 within said chamber 8 and has itsright hand end extending through the bearing 32 with a pinion 10 fixedlymounted on its outer end. A plurality of vanes 7 project from the--sleeve6 within the chamber 8, forming a fan-wheel adapted to exhaustthe air from the drum 1 when in rapid rotation, to carry said air withany chalk dust floating therein through saidchamber 8 and its dependingoutlet conduit 19 to the interior of a dust collector 33 located beneathsaid drum. A ring 5 is seated within the inner end of the chamber 8 andhas an integral inwardly coned part adapted to receive the entering aircurrents passing through the outlets 4 in the drum, to direct sametoward the fanwheel 7.

I have adopted the following means for establishing differential speedsof rotation of the shaft 9 and fan-wheel 7: The numeral 14 denotes abearing sleevefixedly mounted in the right hand frame upright 18, andcontaining arotatable counter-shaft on which is mounted the fixedlyconnected pinion l3 and gear wheel 11, the latter being in mesh with thepinion S on said sleeve 6. A gear wheel 12 is fixedly mounted on theshaft 9 and is in mesh with said pinion 13. The numeral 16 denotes anelectric motor mounted on the bracket 17 of the frame, and whose drivingshaft has a pinion 15 thereon in mesh with said gear wheel 11. It isobvious that by the means of the use of said gear-train, the shaft 9 andsleeve 6 may be rotated at different speeds, the fanwheel 7 beingrotated at a much higher rate of speed than the drum 1. This permits ofthe air being effectively exhausted from the drum 1 while the latter isrotating at a low rate of speed to tumble about any blackboard eraserswhich have been deposited therein through its swinging closure 2.

Either the motor 16 or the hand crank 13 may be used to impart thedifferential rotaconduit 19.

My said apparatus is thus very sanitary for use in school buildings, asno chalk dust can possibly escape into the building.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is:

In combination, a supporting frame, spaced bearings therein, a rotatableshaft mounted in said bearings, means for rotating said shaft, a hollowdrum mounted rotatably non-slidably upon said shaft, said drum having anopening, a closure for said opening, said drum having a clutch-face onone end, a mating clutch-member slidably non-rotatably mounted on saidshaft adapted to be shifted into or out of clutch with the clutch-faceon said drum, said drum having air-inlets in one head, the opformprovided with a plurality of small airoutlets, a cylindrical chamberseated within said cylindrical rentrant part and provided with anair-vent, an air-exhausting rotary fan mounted in said cylindricalchamber, means for rotating said drum and said fan at different speedsof rotation, and an inwardly coned collar seated about the inner face ofsaid fan and adapted to draw the dust-laden air from the drum betweenthe vanes of the fan to be delivered to the vent of said chamberwithout'precipitation in the chamber.

Signed at Waterloo, Iowa, this 16th day of June, 19%.

GRANT U. THOMPSON.

Witnesses:

W. H. BRUNN, GEO. G. KENNEDY.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. (3.

